Industrial process installations are often very complex, utilizing hundreds or even thousands of feet of process fluid pressure piping, as well as a vast array of process devices, such as pumps, valves, process variable transmitters, and many others. Generally, these devices are exposed to process fluid while the process operates.
Pressure transients within the process fluid system can have an adverse on the integrity of pipelines, connected process devices and/or pipeline operations. Actuation of valves or pumps can cause undetected transients (relatively brief spikes in process fluid pressure). These process fluid pressure transients can damage a pipeline and eventually lead to catastrophic failure. Most pressure transients occur without ever being noticed and can cause incremental damage to the pipe structure, protective coatings, thrust restraints, gaskets or seals every time a transient occurs. Accumulated damage of this nature can significantly weaken the system which conveys the process fluid.
Pressure transients can be caused by a number of sources. Pressure transients can occur whenever there is a change in the velocity of process fluid flow. Some causes of process fluid pressure transients include: changes in customer delivery rates; actuation of control valves or similar devices; power outages; and engagement and/or disengagement of process fluid pumps. Some process fluid pressure transients can even exceed the design pressure of a pipe.
Attempts have been made to provide systems that can detect these pressure transients. Such systems have generally been comprised one or more dynamic pressure sensors that are installed in an operating fluid chamber and convey their signals to a signal processor. The signal processor then analyzes the data and displays and output for the operator. Such systems appear to be directed wholly toward detecting and capturing data relative to pressure transients within a pipeline system. Accordingly, in order to employ known pressure transient detection systems, it is necessary to purchase, or otherwise obtain, such systems; disrupt the process while the one or more dynamic pressure sensors are installed therein; and reengage the process thereafter. Further, once the process fluid pressure transient study is complete, such detection systems must generally be removed from the process through similar disruption. This is because current systems are not generally of the type of device suitable for long-term exposure to the environments to which process devices are designed.
Process devices usually have a field-hardened enclosure so that they can be installed outdoors in relatively rugged environments and are able to withstand climatological extremes of temperature, humidity, vibration, mechanical shock, et cetera
Providing the advantages of advanced process fluid pressure transient detection within a process fluid installation without requiring both the additional capital investment and process disruptions of previous methods would represent a significant advance in the field of process fluid control.